Ocean warming and acidification may drag down the commercial Arctic cod fishery by 2100

Abstract

The Arctic Ocean is an early warning system for indicators and effects of climate change. We use a novel combination of experimental and time-series data on effects of ocean warming and acidification on the commercially important Northeast Arctic cod (Gadus morhua) to incorporate these physiological processes into the recruitment model of the fish population. By running an ecological-economic optimization model, we investigate how the interaction of ocean warming, acidification and fishing pressure affects the sustainability of the fishery in terms of ecological, economic, social and consumer-related indicators, ranging from present day conditions up to future climate change scenarios. We find that near-term climate change will benefit the fishery, but under likely future warming and acidification this large fishery is at risk of collapse by the end of the century, even with the best adaptation effort in terms of reduced fishing pressure.

The rapidly changing Arctic and its societal implications

“…Oceanic warming is expected to affect the spatial distribution and productivity of some marine fish species. Lam et al (2016) forecast that Arctic countries are likely to be “winners” under climate change with potential for increased catch, but warming could also diminish stocks due to new predators, invasive species, and oceanic acidification (Crepin et al, 2017; Hansel et al, 2020). New fish species may also migrate north: during abnormally low ice levels in the Chukchi and northern Bering Seas in 2017, for example, the abundance of Arctic cod, pink salmon, walleye pollock, Pacific cod, and northern rock sole was observed to be higher (Huntington et al, 2020).…”

“…Projections suggest, for example, that by 2040 the ice will have receded enough to make gas production feasible in the European off‐shore Arctic under most emission scenarios (Petrick et al, 2017), increased cruise ship tourism offers opportunities for community economic development if well managed (Dawson et al, 2016; Eduard, 2018; Halliday et al, 2018), and opportunities for commercial fisheries are expected to increase with Lam et al (2016) projecting that total fisheries revenue in the Arctic may increase by 39% by 2050 relative to 2000. Hansel et al (2020) caution, however, that after 2050 ocean acidification combined with other stressors could push the North‐East Arctic cod fishery, a large commercial fishery and cornerstone for communities in northern Norway, to collapse even with adaptation efforts. Few studies examine how these potential opportunities are perceived by communities, or factors affecting the ability to capitalize on them, with research mostly on the regional scale (Ng et al, 2018) (exceptions include Dawson et al, 2020; Olsen et al, 2019).…”

Taxing interacting externalities of ocean acidification, global warming, and eutrophication

“…The increase in seawater acidity could lead to important negative effects on the growth of calcifying organisms (Kroeker et al, 2010), but also for noncalcifying fish species (Frommel et al, 2012; Stiasny et al, 2016) implying negative ecological and economic impacts (Cooley & Doney, 2009; Gattuso, 2014; Voss et al, 2015, 2019). Direct impacts on fisheries markets may occur because commercially important global fish populations could decline (Cooley & Doney, 2009; Hänsel et al, 2020; Talmage & Gobler, 2010; Voss et al, 2015, 2019). In addition, nonmarket impacts are possible due to restructuring of ecosystems, biodiversity loss and degradation of coral reefs (Gattuso et al, 2015; Hilmi et al, 2012; Hoegh‐Guldberg et al, 2007; Rodrigues et al, 2015).…”

Satellite Observations Are Needed to Understand Ocean Acidification and Multi-Stressor Impacts on Fish Stocks in a Changing Arctic Ocean

“…Whilst there is debate about the impact of OA on finfish (Kroeker et al, 2013;Haug et al, 2017), there is reasonable evidence from laboratory studies to suggest enough cause for concern (Frommel et al, 2012;Stiasny et al, 2016Stiasny et al, , 2018Stiasny et al, , 2019Dahlke et al, 2017; Supplementary Table 1) and that the changing carbonate chemistry needs to be considered when assessing future fish stocks (Voss et al, 2019). Atlantic cod is the highest landed and most economically valued wild captured species in the Arctic (Pauly et al, 2020) and recent work predicts that although near-future conditions will at first be advantageous to the Atlantic cod (Gadus morchua) fishery in the Northeast Arctic due to reaching the optimal temperature for the spawning stock, once that optimal temperature is reached, further temperature rise combined with OA will lead to a steep decline in stock levels, and by year 2100 the fishery will be at risk of collapse (Hänsel et al, 2020).…”

“…We do this by conducting a literature review, the results of which are primarily single species laboratory studies investigating the impact of OA and other combined stressors. These laboratory studies have their own limitations, and there are still large uncertainties regarding how to scale-up from a single species to ecosystem level (Hänsel et al, 2020). Here we discuss the major knowledge gaps, including some of the caveats of laboratory studies, before putting forward a roadmap of how to close those gaps using satellite observations as an additional tool.…”